GOES-16 (GOES-East) Upper-level Water Vapor (6.2 µm) images (above) displayed the signature of a leeside cold frontal gravity wave (reference) as it moved rapidly southward across the Plains (surface analyses) on 14 January 2021. Post-frontal wind gusts in the 50-70 knot range were seen, with a peak gust to 91 knots (105 mph) in eastern Wyoming.

In addition, an anomalously-strong (170-180 knot) meridional branch of the upper-tropospheric polar jet stream was progressing southward over the Rocky Mountains — and GOES-16 Water Vapor images with plots of Derived Motion Winds and contours of RAP40 model maximum wind speeds (below) revealed that the highest satellite-tracked Derived Motion Wind (DMW) speed was 182 knots over southern Montana at 1401 UTC. Some of the DMW speeds were nearly 10 knots faster than the RAP40 model maximum wind (for example, this 170-knot DMW over Wyoming at 1616 UTC).

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The CIMSS CSPP-Powered GeoSphere site is now available.  This site allows quick access to GOES-16 imagery via Cloud-friendly, flexible (and configurable) software.  Data are accessed from the GOES Re-Broadcast (GRB) downloaded via antenna at CIMSS/SSEC.  Significant effort was made to reduce latency.  For example,  GOES-16 Mesoscale Sectors load within about a minute of their being downloaded, CONUS sectors load within about 8 minutes, and Full-Disk imagery loads within 20 minutes.  In addition to the individual bands (1-16), a sharpened True-Color (Daytime) and Nighttime Microphysics (Nighttime) product is available.  The data are tiled and only tiles that are needed for the present view are loaded.  In addition to still images, animations can be displayed, and a user can choose how many images are in the loop (up to 30), and what the time-step (i.e., ‘Pattern Stride’) is.  Users can also share urls so that others can view the same animation.  For example, the image above was created with this url.  Individual frames can be downloaded via a left-click on the image.  There is at present no method to download animations directly.

More information on this site is available in this recorded presentation created from this PowerPoint.

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GOES-16 (GOES-East) Nighttime Microphysics RGB, Night Fog BTD (10.3-3.9 µm) and Cloud Thickness product (above) showed an arc of relatively thin fog across northern South Carolina, eastern North Carolina and southeastern Virginia — which was becoming thicker/deeper in time during the hours leading up to sunrise on 13 January 2021. In areas where the Cloud Thickness increased to 400 meters or more (lighter shades of cyan), freezing fog was observed at nearby METAR sites.

GOES-16 Nighttime Microphysics RGB images with plots of surface observations (below) indicated that air temperatures were near or just below freezing at most sites across the region.

The band of fog over eastern North Carolina and southeastern Virginia was being pushed eastward by a lower-tropospheric trough, as shown by the NAM40 model 925 hPa wind field at 12 UTC (below).

After sunrise, GOES-16 “Red” Visible (0.64 µm) images (below) showed that most of the fog quickly dissipated across southeastern Virginia and eastern North Carolina, while thicker fog persisted over much of South Carolina.

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GOES-16 (GOES-East) Mid-level Water Vapor (6.9 µm) images (above) showed widespread precipitation that was developing across the southern High Plains and Lower Mississippi Valley on 10 January 2021. A closed middle-tropospheric low was providing forcing for ascent as it moved eastward across the region — and its cyclonic circulation was evident in the Water Vapor imagery. Storm total snowfall accumulations were as high as 11 inches in Texas, 8 inches in New Mexico, 6.5 inches in Louisiana and 4.5 inches in Mississippi.

GOES-16 Day Cloud Phase Distinction RGB images (below) revealed pockets of banded convection, whose glaciated cloud tops appeared as shades of green to yellow.

===== 11 January Update =====

On the following day, gaps in low-level cloud cover allowed the areal extent of resulting snow cover to be seen in GOES-16 Day Cloud Phase Distinction (snow = brighter shades of green) and Day Snow-Fog (snow = darker shades of red) RGB images (above).

A toggle between VIIRS True Color and False Color RGB images from Suomi NPP at 1936 UTC (below) provided another example of a RGB variant that is useful for the discrimination of low cloud vs. snow — snow cover appeared as shades of cyan in the False Color image.

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